Re: [patch] ACPI: update debug parameter documentation

[Bjorn Helgaas <bjorn.helgaas@hp.com>]

On Monday 27 October 2008 03:40:45 pm Bjorn Helgaas wrote:
> [I posted this earlier: http://marc.info/?l=linux-acpi&m=121736785510685&w=2
>  but somehow only half of it made it.  Here's the rest.]
> 
> Reformat acpi.debug_layer and acpi.debug_level documentation so it's
> readable, add some clues about how to figure out the mask bits that
> enable a given ACPI_DEBUG_PRINT statement, and include a couple useful
> examples.

Ignore this for now.  Myron pointed out that "acpi.debug_layer=" doesn't
work on the kernel command line.  And the examples, which I remember
testing once, don't work.  Sigh.

I'll fix it so it actually makes sense.

> Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
> 
> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
> index 343e0f0..8d17859 100644
> --- a/Documentation/kernel-parameters.txt
> +++ b/Documentation/kernel-parameters.txt
> @@ -201,26 +201,50 @@ and is between 256 and 4096 characters. It is defined in the file
>  	acpi.debug_layer=	[HW,ACPI]
>  			Format: <int>
>  			Each bit of the <int> indicates an ACPI debug layer,
> -			1: enable, 0: disable. It is useful for boot time
> -			debugging. After system has booted up, it can be set
> -			via /sys/module/acpi/parameters/debug_layer.
> -			CONFIG_ACPI_DEBUG must be enabled for this to produce any output.
> -			Available bits (add the numbers together) to enable debug output
> -			for specific parts of the ACPI subsystem:
> -			0x01 utilities 0x02 hardware 0x04 events 0x08 tables
> -			0x10 namespace 0x20 parser 0x40 dispatcher
> -			0x80 executer 0x100 resources 0x200 acpica debugger
> -			0x400 os services 0x800 acpica disassembler.
> -			The number can be in decimal or prefixed with 0x in hex.
> -			Warning: Many of these options can produce a lot of
> -			output and make your system unusable. Be very careful.
> +			which corresponds to the _COMPONENT definition in
> +			ACPI source files.  After system has booted, this mask
> +			can be set via /sys/module/acpi/parameters/debug_layer.
> +
> +			CONFIG_ACPI_DEBUG must be enabled for this to produce
> +			any output.  The number can be in decimal or prefixed
> +			with 0x in hex.  Some of these options produce so much
> +			output that the system is unusable.
> +
> +			The following are some of the global components
> +			defined by the ACPI CA and the Linux OSPM:
> +				0x01 utilities
> +				0x02 hardware
> +				0x04 events
> +				0x08 tables
> +				0x10 namespace
> +				0x20 parser
> +				0x40 dispatcher
> +				0x80 executer
> +			       0x100 resources
> +			       0x200 ACPI CA debugger
> +			       0x400 OS services
> +			       0x800 ACPI CA disassembler
> +			     0x40000 battery
> +			     0x80000 button
> +			    0x200000 fan
> +			    0x400000 PCI
> +			  0x10000000 bay
> +
> +			Many others, e.g., ACPI_BUS_COMPONENT and
> +			ACPI_AC_COMPONENT, are defined by the Linux OSPM and
> +			individual drivers.
> +
> +			For debugging PCI/_PRT issues (PCI, info msgs):
> +			    acpi.debug_layer=0x400000 acpi.debug_level=0x10
> +			For ACPI hardware issues (hardware, all msgs):
> +			    acpi.debug_layer=0x2 acpi.debug_level=0xffffffff
>  
>  	acpi.debug_level=	[HW,ACPI]
>  			Format: <int>
>  			Each bit of the <int> indicates an ACPI debug level,
>  			which corresponds to the level in an ACPI_DEBUG_PRINT
> -			statement.  After system has booted up, this mask
> -			can be set via /sys/module/acpi/parameters/debug_level.
> +			statement.  After system has booted, this mask can be
> +			set via /sys/module/acpi/parameters/debug_level.
>  
>  			CONFIG_ACPI_DEBUG must be enabled for this to produce
>  			any output.  The number can be in decimal or prefixed
> @@ -248,9 +272,6 @@ and is between 256 and 4096 characters. It is defined in the file
>  			    0x10000 resources
>  			    0x20000 user requests
>  			    0x40000 package
> - 			The number can be in decimal or prefixed with 0x in hex.
> - 			Warning: Many of these options can produce a lot of
> - 			output and make your system unusable. Be very careful.
>  
>   	acpi.power_nocheck=	[HW,ACPI]
>   			Format: 1/0 enable/disable the check of power state.
>